Which of the Following Transactions Is Most Likely Considered Part

Which of the following transactions is most likely considered part of the informal economy?

A) Tracy accepting only cash payments for the salon services she offers so that she can understate her income
B) Tom holding a garage sale to dispose of his old toys and buy new toys with the money collected from the sale
C) Jonathan converting all his gold possessions into cash
D) Cathy offering to mow the lawn of the neighbor who helped her clean her swimming pool
E) Daisy buying a boat even though the interest paid on a boat loan is not tax-deductible